The present invention is related to electromechanical brake systems, and in particular to combined thrust bearing/load cells for electric brake actuators.
Electromechanical brakes for aircraft comprise stator discs and rotor discs. The stator discs are coupled to an axle and do not rotate relative to the axle. The rotor discs are coupled to, and rotate with the wheel, relative to the axle. An electric brake actuator is utilized to apply force to all of the stator discs, which in series, compress the stator portion with the rotor portion of the brake. This creates friction that slows the rotation of the wheel, converting kinetic energy into thermal energy. In order to better control the actuator, it is desirable to know the real/non-estimated force that is being applied to the stator disc by the actuator.
Load cells in electric brakes are often used to determine strains experienced by the actuator when applying force to the stator discs. These actuators are sometimes circular in shape and thus, measuring devices placed in the reactionary load path to measure axial compression will experience bending and hoop stresses, which can cause measurement inaccuracies. Load cells, being in the direct load path, take up space within the actuator, increasing the weight, and requiring a greater axial length of the actuator itself. It is desirable to reduce the bending and hoop stresses experienced by the measuring devices implemented on circular load cells while also reducing weight and space taken up by a load cell within the actuator.